Mapping the spawning grounds of North Sea cod ( Gadus morhua ) by direct and indirect means
نویسندگان
چکیده
منابع مشابه
Mapping the spawning grounds of North Sea cod (Gadus morhua) by direct and indirect means.
Despite recent evidence for sub-stock structuring, North Sea cod are assessed as a single unit. As a consequence, knowledge of sub-stock trends is poor. In particular, there are no recent evaluations of which spawning grounds are active. Here we report results from the first ichthyoplankton survey to cover the whole North Sea. Also, this survey, conducted in 2004, was the first to make extensiv...
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We investigated growth patterns and evidence of growth dependent survival for a population of Atlantic cod Gadus morhua using analysis of their otolith microstructure. Central concentrations of a population of cod larvae and juveniles in the north-eastern North Sea were sampled twice (in April and May 2001), and larval/juvenile growth history from each of the sampling sequences was outlined. Gr...
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Farmed Atlantic cod Gadus morhua have been hypothesized to pose a risk to the natural environment through escape of fish or release of their gametes from sea cages. The use of sterile triploids has been suggested as a way to prevent spawning of farmed fish, whether escaped from their cages or still contained within them. This laboratory study examined the reproductive potential of triploid male...
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ژورنال
عنوان ژورنال: Proceedings of the Royal Society B: Biological Sciences
سال: 2008
ISSN: 0962-8452,1471-2954
DOI: 10.1098/rspb.2008.0201